Prof. R. B. Patil
( JJMCOE, Jaysingpur)
1. Aesthetics: Aesthetic is defined as a set of principles of appreciation of beauty.
1.1.Aesthetic is deals with the appearance of the product. Appearance is the outward expression of
quality of the product and is the first communication of the product with the user is nothing but
the appearance of the product.
1.2.Now days, number of products available in the market are having most of the parameters
identical, so the appearance of the product plays a major role in attracting the customer.
1.3.To compete and succeed in the market place, manufacturers will have to look beyond reliability
and physical quality, and pay more and more attention to the aesthetic and subjective quality of
the product.
1.4.Aesthetic quality and cannot be separated from the product quality.
2. The parameters that are normally considered by the customer while selecting
the products are:
Each product is to be designed to perform a specific function or a set of function to the satisfaction of
the customer. Some of the important parameters are as given below.
2.1.Functional performance.
2.2.Durability.
2.3.Initial costs.
2.4.Running costs.
2.5.Ability to withstand adverse condition.
2.6.Comfort to user.
2.7.Aesthetic and ergonomic considerations.
3. Guidelines in Aesthetic Design:3.1.The appearance should contribute to the performance of the product. Example, the aerodynamic
shape of the car will have a lesser air resistance, resulting in lesser fuel consumption.
3.2.The appearance should reflect the function of the product. Example, the aerodynamic shape
indicates the speed.
3.3.The appearance should reflect the quality of the product. Example, the robust and heavy
appearance of the hydraulic press reflects its strength and rigidity.
3.4.The appearance should not be at too much of extra cost unless it is a prime requirement.
3.5.The appearance should be achieved by the effective and economical use of materials.
3.6.The appearance should be suitable to the environment in which the product is used.
Aesthetic and Ergonomic considerations in Design (Year 2012-13)
Page 1
Prof. R. B. Patil
( JJMCOE, Jaysingpur)
4. Aspects of Aesthetic Design:4.1.Form (Shape):-form is the image presented by the outer surface of an object or structure. There
are 05 basic types of the products namely, step, taper, shear, streamline and sculpture as shown in
fig.
a. Step form: - structure having vertical ascent. Ex. Multi-storey building.
b. Taper form: - It consists of tapered blocks or taper cylinders.
c. Shear form: - It has a square outlet.
d. Streamline form: - It has a streamlined shape having a smoothflow as seen in automobile
and aeroplane structures.
e. Sculpture form:- It consists of ellipsoids, paraboloids and hyperboloids.
4.2.Symmetry and Balance:-
a. Most of the life forms in the nature are approximately about at least one axis.
b. The human eye is thus conditioned to see the things in symmetrical form and tends to reject
asymmetrical shapes as ugly.
c. Hence in many products, symmetry about at least one axis improves the aesthetic appeal of
the product.
d. However, wherever functional requirement demands asymmetry, balance in the product
improves the aesthetic feeling.
e. Fig. shows three arrangements of a control panel:
1) Arrangement (a): It is symmetrical but is ergonomically poor, as control knobs are placed on
either side of the panel.
2) Arrangement (b): It is ergonomically good but looks unbalanced because bulk of the display
mass is towards the right of the panel, and hence aesthetically poor.
3) Arrangement (c): It is ergonomically good as well as aesthetically pleasing because of the sence
of balance of mass about the central axis.
4.3.Colour:-
 Colour is one of the major contributors to the aesthetic appeal of the product. Many colours
are linked with different moods and conditions.
 The selection of the colour should be compatible with the conventions. Morgan has suggested
the colour code given in table.
Colour
Meaning
Red
Orange
Yellow
Green
Blue
Grey
Danger, Hot
Possible danger
Caution
Safe
Cold
Dull
Aesthetic and Ergonomic considerations in Design (Year 2012-13)
Page 2
Prof. R. B. Patil
( JJMCOE, Jaysingpur)
4.4.Continuity: A product which has good continuity of elements is aesthetically appealing.
 For example, a fillet radius at the change of cross section adds the continuity to the product,
and hence improves the appearance as shown in fig.
4.5.Variety: Variety is particularly useful while marketing the range of products. The variety relieves the
user of the boredom.
 For example, in consumer appliances, the functionally identical products are manufactured in
a number of varieties by a single manufacturer.
4.6.Proportion: Proportion is concerned with the relationship, in size, between connected items or elements of
items.
 The product which is out of proportion is not aesthetically pleasing.
 Normally, the proportions of the products are developed from the sound functional
requirements, but can sometimes override the functional aspects.
 The spanner, shown in fig satisfies the functional requirements and is also easy to
manufacture. But it is out of proportion, and hence poor in appearance.
 The spanner shown in fig. is in proportion and aesthetically pleasing.
4.7.Contrast: Contrast is a distinction between the adjacent elements of the product which have clearly
different characteristic and functions.
 The contrast improves the aesthetic appeal of the product.
4.8.Impression and purpose:



The product not only should look nice but also should look as if it will work.
The product should give the impression of the satisfactory performance or purpose.
The taper shape gives the impression of strength and stability as shown in fig. resp.
Similarly, the streamline shape gives the impression of speed.
4.9.Style: Style is a visual quality of the product which sets it apart from the rest of the functionally
identical products.
 Good style will skilfully reflect a current public mood, which may be influenced by the
technological developments, or by a prevailing social or environmental climate.
Aesthetic and Ergonomic considerations in Design (Year 2012-13)
Page 3
Prof. R. B. Patil
( JJMCOE, Jaysingpur)
4.10. Material and surface finish: The material and surface finish of the product contribute significantly to the appearance.
 The material like, stainless steel gives better appearance than the C.I., plain carbon steel or low
alloy steels.
 The brass or bronze give richness to the appearance of the product.
 The products with better surface finish are always aesthetically pleasing.
 The surface coating processes like, spray painting, anodizing, electroplating, etc. greatly
enhances the aesthetic appeal of product.
4.11. Tolerances: Proper tolerance of the mating parts improves the aesthetic appeal of the product.
 Unwanted clearance or interference hampers the aesthetic appeal.
4.12. Noise: Unwanted noise is disturbing and is suggestive of some malfunction within the product, and
hence it greatly reduces the aesthetic appeal.
5. Ergonomic Considerations in Design: The word Ergonomic is formed from two greek word “Ergon (work)” and “Nomos(natural laws)”.
 Ergonomics is defined as the scientific study of the man – machine - working environment
relationship and the application of anatomical, physiological and psychological principles to solve
the problems arising from this relationship.
 The final objective of the ergonomic is to make the machine fit for the user rather than to make the
user adapt himself or herself to the machine.
 It aims at decreasing the physical and mental stresses to the user.
6. Areas covered under Ergonomics:The different area covered under the ergonomics is as follows.
 Communication between man (User) and machine.
 Working environment.
 Human anatomy and posture while using the machine.
 Energy expenditure in hand and foot operations.
Aesthetic and Ergonomic considerations in Design (Year 2012-13)
Page 4
Prof. R. B. Patil
( JJMCOE, Jaysingpur)
7. Communication between Man (user) and machine: Man – machine closed loop system and its working is shown in figure.
 User or man receives the information displayed on the display through the sense of organs.
 Based on the situation or condition, he or she will take the appropriate action using hand or
feet.
 The effective working of this man – machine closed loop system is affected by lightening,
noise, temperature, humidity, air circulation etc.
 The communication between man and machine is carried through displays and controls.
 This general man – machine closed loop is applicable to any type of system which is
manually operated or semi- automatic.
8. Design of Displays:Design considerations:1. The scale should be clear and legible.
2. The scale should be divided in a linear progression such as 10-20-30-40-……. And not as 5-12-3045……..
3. The number of subdivisions between the numbered divisions should be as minimum as possible.
4. The vertical numbers should be used for the moving pointer type display with circular disc.
5. The numbering should be in clockwise direction on a circular scale.
6. The pointer should have knife edge with a mirror in a dial to minimize the parallax error while taking
the reading.
7. Whenever the straight scales are to be used, the horizontal scales are preferred over the vertical scales
because the vertical scales are more prone to the reading error.
8. When a display and its associated control are to be placed near each other, the control device should
be placed either below or to the right of the display.
9. The size of the or letter on the scale should be taken as,
Height of the Number or letter >= (Reading distance / 200)
The display devices are classified into two groups:
8.1.Qualitative display.
8.2.Quantitative display
A. Qualitative Display: -the displays which indicate only the condition or state without giving the
values are known as Qualitative display.
Aesthetic and Ergonomic considerations in Design (Year 2012-13)
Page 5
Prof. R. B. Patil
( JJMCOE, Jaysingpur)
 Examples, traffic signals, on-off indicators.
 Types of qualitative displays.
 Circular dial.
 Straight legend.
 Coloured lights.
B. Quantitative Display: -the display which give the quantitative measurements or numerical
information are known as quantitative displays.
 Examples, voltmeter, ammeter, speedometer, watches, energy meter etc.
 Types of quantitative displays.
 Moving pointer – fixed scale type display.
 Fixed pointer – movable scale type display.
 Digital display.
9. Design of controls:Ergonomic considerations in design of controls:1. The control devise should be logically positioned and easily accessible.
2. The control operation should involve minimum and smooth moments.
3. The operation should consume minimum energy.
4. The portion of the control device which contact with users hand should be in comfort with the
anatomy of human hands.
5. The proper colours should be used for control devices and backgrounds so as to give the required
psychological effects.
6. The shape and size should be compact.
The anthropometric and functional anatomy data is used while designing the control members. Some
of the control members are as discussed below.
a. Design of Push Button: - A push button is a reciprocating control which has positive action only in
one direction. It is operated by finger. The top surface of push button is slightly concave. Pressing
force = 0.3 to 1.2 kgf. Button diameter = 12 to 15mm. movement distance = 3 to 10mm. distance
between adjacent push button should be at least 6mm. Stop push button is made larger than the others
and of size up to 25mm. Also painted red colour.
b. Design of Toggle switches: - used in light duty electrical switching operations. Diameter = 3 to
12mm. length = 12 to 25mm. generally mounted in vertical position. Movement required 30 to 40
degree on both side. Placed in horizontal row.
Aesthetic and Ergonomic considerations in Design (Year 2012-13)
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Prof. R. B. Patil
( JJMCOE, Jaysingpur)
c. Design of Knobs:-knobs are control members which can be operated freely by gripping with the
fingers of one hand. It is continuous function type, making fine adjustment and used as selector.
1.
Manipulated by two or three fingers
Diameter = 10 -30 mm
Depth = 12-25mm.
2.
Manipulated by whole hand
Diameter = 35-75 mm
Depth = 20-50mm.
d. Design of Cranks:- It is used for providing the torque by hands. It is used when turning speed is up
to 200 rpm, when rapid complete turns are required, when heavy loads are to be moved manually.
They are not mounted permanently on the shaft.
Sr. No.
Load, kgf
Rpm
Length
1.
2.5
150-200
60-75
2.
2.5
200
25-50
3.
15
100
110
4.
25
20
500
e. Design of Levers: - A lever is a rod-like control working in one direction about a fulcrum. Length of
travel is small. Fast movement of travel is required. Load is medium to heavy. Travel should not be
more than 175mm and handle of the lever is so placed that the arm of the operator is straight at the
end of travel. Operated by single hand.
f. Design of Hand wheel: -A hand wheel is a circular control member which is gripped by the rim or
the handle during operation. It is used when, turning speed is low (up to 1 rpm), accurate partial
turning is required, and torque required is greater than 20kgf.
Sr. No.
Torque Resistance
Wheel diameter
1.
25-50
150
2.
50-75
250
3.
75-110
250
4.
>110
400
g. Design of rotary lever: - A rotary is a lever attached to a shaft to permit a complete turn. It is used
fairly high force.
h. Foot pedal: - it is used as fast controls for medium to large operating loads.
i. Star wheel: - it consists of three or more lever attached to a shaft. Force required is more than the
hand wheel (15%).
j. Joystick:- it is fast, coarse and simultaneous two dimensional for light operating loads. They are
used in CNC machines and computers.
Aesthetic and Ergonomic considerations in Design (Year 2012-13)
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Prof. R. B. Patil
10.
( JJMCOE, Jaysingpur)
Layout of panels
The layout of the control panel should increase the effectiveness and efficiency of the user or operator.
Some of the general guidelines for the layout of the panel are as follows.
1. Sequence of operation: When a machine is controlled by the sequential operation of a number of control devices,
the controls and displays should be arranged in the sequence of operation.
 This makes the operation easier and convenient for the user.
2. Functional Grouping:  Certain controls or displays are associated with a particular function. Such controls or
displays should be grouped together.
 Example, a motor car controls are mounted on the steering column and those controls are
related to warning or signalling to others ( driving lights, direction indicators, horn etc.)
are grouped together.
3. Related control arrangement: For the ease of identification, the arrangement of group of controls should be the same as
the devises controlled by them.
 For example, the four controls that operates the four electric hot plates are not readily
identified when arranged as shown in figure but are readily identified when arranged as
shown in figure.
4. Frequency of use: Some controls and displays are used more frequently as compare to others. Such controls
and displays should be placed nearest to the user.
 Example, in a car, the speedometer is placed exactly in front of driver as it is most
frequently read.
5. Easy identification of controls or displays: The controls or displays on the panel should be easily identified by the user. This is the
most easily achieved if they contrast well with the panel face and are arranged in irregular
groups.
11.
Work Environment:
Aesthetic and Ergonomic considerations in Design (Year 2012-13)
Page 8
Prof. R. B. Patil
( JJMCOE, Jaysingpur)
Man machine system is significantly affected by the working environment. Working efficiency and
health of the operator are also affected by the operator. Some of the important factors are as given
below,
11.1. Lightening:
The amount of light required to do a task depends upon the nature of task, the reflective
characteristics of the equipment and the vision of the operator.

Certain codes of practice are available that recommend the amount of light necessary for a
certain task.

To increase the focus of attention on the task area, it is recommended that the light of the
surrounding area must be less than the task area.

Change in the brightness and colour with respect to the surrounding will help to reduce the
fatigue of the operator.

Bright colours on the walls should not be used.
11.2. Noise: The noise at the workplace causes damage the hearing and reduction of the work efficiency.
 Noise caused by the equipment that a person is using is less annoying than others.
 The industrial safety rules specify the acceptable noise level for different work places.
 Noise level can be reduced by proper maintenance, by the use of silencers and by placing
vibrating equipment on isolating mounts.
 If possible use ear plugs.
11.3. Temperature: The worker should not feel too hot or too cold, to perform the task the task efficiently.
 For heavy work – lower temperature, for light work – relatively higher temperature.
 The optimum temperature required is decided by the nature of work. The deviation of the
optimum temperature reduces the efficiency of the operator.
11.4. Humidity and air circulation: At high temperature, humidity affects significantly on the efficiency of the operator.
 At high temperature, the low humidity may cause discomfort due to drying of throat and nose and
high humidity may cause discomfort due to sensation of the stuffiness and over sweating in a illventilated or crowded room.
Aesthetic and Ergonomic considerations in Design (Year 2012-13)
Page 9
Prof. R. B. Patil
( JJMCOE, Jaysingpur)
University Exam Questions
1. Aspects of aesthetic design. Dec. 2011, May 2011, Dec. 2012
2. Explain the relationship between man, machine and environment. Dec. 2010, 09,05,09
3. Explain following with respect to aesthetic design, 1) form, 1) symmetry and balance, 3) colour, 4)
style. Dec. 2010
4. Layout of display and control in a panel. Dec. 2010
5. Describe creative design process. Dec. 2009
6. Ergonomic considerations in design of displays and controls. Dec 2011
7. Discuss with suitable example “Form follows function”. Dec 2011
8. Explain the ergonomic considerations applied to location of displays and control members. Dec.
2007
9. Explain the importance of following factor applied in product design aesthetic sensibility, 1) line 2)
shape 3) colour 4) form. Dec. 2008
10. Explain with suitable example; explain effect of appearance, shape, colour and quality in aesthetic
design. May 2010,2009, 2006
11. Explain the ergonomic considerations in following items, 1) control knobs, 2) hand wheel. May
2010, 08
12. Explain basic forms of product. Dec. 2005, 08, 06
13. Discuss ergonomic design consideration involved in the design of handle bar control of a two
wheeler. 2006
14. Explain brainstorming technique used in creative design. 2008, 2006, 2009
15. Explain with neat sketches, various displays in ergonomic design. 2006
16. With suitable example, explain importance of Ergonomic consideration in the product design. May
2011.
17. With the help of suitable examples, explain the importance of aesthetic consideration in the product
design. Dec.2012
18.
Aesthetic and Ergonomic considerations in Design (Year 2012-13)
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